Create PyVenvRunner.cs

StabilityMatrix/PyVenvRunner.cs

@@ -0,0 +1,92 @@
+using System;
+using System.Diagnostics;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace StabilityMatrix;
+
+/// <summary>
+/// Python runner using a subprocess, mainly for venv support.
+/// </summary>
+public class PyVenvRunner: IDisposable
+{
+    public Process? Process { get; private set; }
+    private ProcessStartInfo StartInfo => new()
+    {
+        FileName = PythonPath,
+        UseShellExecute = false,
+        RedirectStandardOutput = true,
+        CreateNoWindow = true
+    };
+    public string RootPath { get; private set; }
+    
+    public event EventHandler<string> OnStdoutUpdate;
+
+    public PyVenvRunner(string path)
+    {
+        RootPath = path;
+        OnStdoutUpdate += (_, _) => { };
+    }
+    
+    // Whether the activate script exists
+    public bool Exists() => System.IO.File.Exists(RootPath + "Scripts/activate");
+    
+    /// <summary>
+    /// The path to the python executable.
+    /// </summary>
+    public string PythonPath => RootPath + @"\Scripts\python.exe";
+
+    /// <summary>
+    /// Configures the venv at path.
+    /// </summary>
+    public async Task Setup(bool existsOk = false)
+    {
+        if (!existsOk && Exists())
+        {
+            throw new InvalidOperationException("Venv already exists");
+        }
+        
+        // Create RootPath if it doesn't exist
+        if (!System.IO.Directory.Exists(RootPath))
+        {
+            System.IO.Directory.CreateDirectory(RootPath);
+        }
+
+        await PyRunner.Exec(@"
+import venv
+venv.EnvBuilder(with_pip=True).create(r""" + RootPath + @""")
+        ");
+    }
+
+    public void RunDetached(string arguments)
+    {
+        this.Process = new Process();
+        Process.StartInfo = StartInfo;
+        Process.StartInfo.Arguments = arguments;
+        
+        // Bind output data event
+        Process.OutputDataReceived += OnProcessOutputReceived;
+        
+        // Start the process
+        Process.Start();
+        Process.BeginOutputReadLine();
+    }
+
+    /// <summary>
+    /// Called on process output data.
+    /// </summary>
+    private void OnProcessOutputReceived(object sender, DataReceivedEventArgs e)
+    {
+        var data = e.Data;
+        if (!string.IsNullOrEmpty(data))
+        {
+            OnStdoutUpdate?.Invoke(this, data);
+        }
+    }
+
+    public void Dispose()
+    {
+        Process?.Dispose();
+        GC.SuppressFinalize(this);
+    }
+}